Synthesis and Biological Evaluation of Some Novel Quinolinone Derivatives

Abstract

The research work in this thesis focused on synthesis of 6-butyl-3- [(dimethylamino)methylene]-3H-pyrano[3,2-c]quinoline-2,4,5(6H)-trione (2), 6-butyl-5,6-dihydro-4-hydroxy-2,5-dioxo-2H-pyrano[3,2-c]quinoline -3-carbonitrile (12), and ethyl 2-(6-ethyl-4,5-dioxo-pyrano[3,2-c] quinolin-3-yl)-2-oxoacetate (20) as the key compounds. The chemical reactivity of these new precursors towards different nucleophiles was studied. The new products were screened for their antioxidant activity.

Part I. Synthesis of some novel heteroannulated pyrano[3,2-c]quinoline-2,5(6H)-diones

Herein we report the synthesis of the novel 6-butyl-3- [(dimethylamino)methylene]-3H-pyrano[3,2-c]quinoline-2,4,5(6H)-trione (2), 6-butyl-5,6-dihydro-4-hydroxy-2,5-dioxo-2H-pyrano[3,2-c]quinoline- 3-carbonitrile (12), and study of their chemical behavior towards different nucleophiles to obtain some novel heteroannulated pyrano[3,2-c] quinolone derivatives from heterocyclization reactions with various binucleophiles.

A clean reaction of N-butylaniline with two equivalents of diethyl malonate under solvent-free conditions gave 4-hydroxypyrano[3,2-c] quinoline-2,5(6H)-dione (1). The desired 3-[(dimethylamino)methylene] pyrano[3,2-c]quinolinone derivative 2 was prepared via thermal condensation of the pyranoquinolinone 1 with dimethylformamide- dimethylacetal.